GISS Global Land-Ocean Temperature Index Vs GHCN

This is the state of the world’s surface temperatures according to NASA’s Goddard Institute for Space Studies from 1880 through 2017. It is indeed a very bleak picture. As I see it, this is showing an exponential rise in temperatures starting at the beginning of the 20th century.

Of course, I am curious as to what this means exactly. As I have said before, looking at an average over time is certainly a valid way to do things, but it often fails to tell the full story.

Fortunately, NASA provides a visualization of the five year average variation of global surface temperatures. It doesn’t show what years you are looking at specifically within the time series, but you get the general idea.

The time series certainly does depict a bleak picture as well, especially for the most northerly areas of the northern hemisphere. Obviously, I don’t know how accurate this truly is or how accurate it is meant to be. However, taken at face value it would appear the US, Canada, and Europe are all facing temperature increases of 2° F to 3° F above the 1951 – 1980 average. Which is fortunate for me, because the long term data I have pulled from the GHCN covers those areas, though mainly the US. A dramatic trend such as this which heavily affects the very area where most of the data originates should be easily discernable.

The following charts cover 490 stations in the GHCN reporting continuously from 1900 through 2011. Most of these stations are in the US, though Canada, Australia, and Europe are represented. This is a substantial sampling of stations which indicate the number of warm days and extremely hot days have been steadily declining since the early 1940’s.

The next charts cover the daily high and low temperatures for the hottest month of the year and the coldest month of the year for 1067 stations reporting continuously from 1920 through 2011. Both charts also show high temperatures steadily declining since the early 1940’s just as the preceding charts. Both charts also show a steady increase in the daily low temperatures.

What is interesting to me is the 1930’s warming shows quite clearly in the chart of the annual warmest month but it does not do so in the chart of the coldest month. It appears that period of extreme high temperatures was accompanied by a series of extremely harsh winters. Winters cold enough to rival the coldest of the 1970’s. Similarly, the 1950’s through the 1970’s cooling period shows quite clearly in the chart of the coldest month but is not apparent in the chart of the warmest month.

One other interesting observation is how the coldest month varies so much more than the warmest month. The amount of year to year variation for the coldest month is nearly double that of the warmest month. I intentionally scaled the two graphs to the same 13° interval to highlight just how different the variation is.

The preceding charts from the GHCN depict data which simply does not accord with the GISS data. They certainly do not accord with the time series representation of the history of the US, Canada and Europe. GISS appears to have mostly done away with the 1930s warming. The 1950s through 1970s cooling appears to be gone. The post 1980s warming has disappeared as an individual trend in time, it has been now become just a portion of a curve proceeding uninterrupted from the mid 1940’s.

The post 1940’s warming shown by GISS is not reflected in the temperatures of the warmest month or the coldest month of the year. The post 1980’s warming trend evident in the coldest month does not follow the exponential pattern in the GISS chart. The rate of warming during this month clearly slowed down past the mid 90’s and appears to show a decided cooling trend since 2006. There has been no increase in warm or hot days.

So how, exactly, have the more northerly latitudes warmed in the exponential and supposedly dangerous fashion depicted by GISS? The indication is the hottest months of summer have become milder instead of hotter. It does appear the number of excessively harsh winters has fallen to practically zero, at least as of 2011. Perhaps, in addition to becoming milder, summer is now lasting longer. Perhaps, since winter has also become milder, spring is arriving sooner. Longer, milder summers and shorter, milder winters would usually be considered good things. If that is indeed the case any resulting increase in annual temperature averages should likewise be considered in the same light.

I am not really seeing good weather as a valid reason to increase taxes, drive up energy costs, degrade economies, cede our sovereignty to some world government, cover huge plots of land with bird and bat shredders, or to forbid the poorest nations on the planet the means to lift their people out of poverty.